Broadway is drawing a whole new crowd — nostalgic hoops fans. Kyran Bent (center) joined his sons Kieran (left) and Michael at “Magic/Bird,”based on the lives of Celtic great Larry Bird and Laker legend Magic Johnson.N.Y. Post: Astrid Stawiarz

The four men milling around the Longacre Theater in casual button-down shirts looked as if they’d be more comfortable outside Madison Square Garden — but no, they didn’t take a wrong turn at Penn Station.

The 33-year old Larry Bird fanatic had just seen “Magic/Bird” with his pals, who played high-school basketball together.

“We’ve gone to the theater with our wives and girlfriends but never with other dudes,” Frayler adds. “It’s a real man-wich in there!”

They’re not alone. Guys whose idea of theater generally involves a ball, a beer and a Jumbotron are turning the area around 48th Street’s Longacre Theater, where “Magic/Bird” opens Wednesday, into testosterone alley.

Not since “Lombardi” had men lining up outside the Circle in the Square Theatre for eight months have so many non-theater-going sports fans headed for Broadway.

Written by Eric Simonson and produced by Fran Kirmser and Tony Ponturo — the team behind “Lombardi” — the play explores the intense rivalry and unlikely friendship between Celtic great Larry Bird and Laker legend Earvin “Magic” Johnson.

Not surprisingly, a lot of theatergoers are wearing their hearts on their sleeves.

“There’s a lot of Lakers and Celtics jerseys walking into the theater,” Kirmser says. “There’s also a lot of Knicks jerseys.” She says other producers have congratulated them on luring fresh blood to Broadway.

“We’ve seen groups of corporate men come in suits after work. They’ve clearly left work together to come see it. It’s really cool.”

Frayler’s buddy, 33-year-old Billy Trudden, a mortician, saw a chance to relive his own rivalry with his pal.

“As soon as I knew this was coming out, I said we need four seats,” says Trudden, a Magic fan. “Two for me and Scott, and two for the guys that have to sit between us,” he jokes.

Some men travel a lot farther than Long Island to get their nostalgia fix.

Kyran Bent came down from Cape Cod to celebrate his 67th birthday by seeing “Magic/Bird” with his sons, Michael and Kieran Bent.

“Last year we took him to see ‘Lombardi,’ ” says Kieran, 32. “We wouldn’t have gotten him down here from the Cape for any old show.”

The production — which stars the 6-foot-5 actors Tug Coker as Larry Bird and Kevin Daniels as Magic Johnson — follows the players from their college days through their NBA careers and the 1992 Olympic Dream Team.

Their bicoastal battles dominated and defined the NBA landscape in the ’80s and gave sports fans some of their most powerful touchstones.

The show’s most poignant moment is Magic Johnson’s stunning revelation that he had the HIV virus — a scene that sent tears down the elder Bent’s face.

“I was literally crying in there,” he says. “Magic was so great and you didn’t know if he would make it.” He and his sons can still remember where they were when they heard Johnson’s announcement, which he made 20 years ago.

Mark Johnson, a 47-year-old professor and lifelong Lakers fan now living in Brooklyn, was in grad school at Columbia back then. He was so upset, he couldn’t leave his apartment.

“This play is a must-see just because I remember all of this well,” said Johnson, who grew up in southern California. “Magic and Bird had such a great synchronicity in their rivalry. Imagine these two guys who are the perfect counterpoint to each other, and they join the two teams that were rivals. It was perfect.”

Johnson plans to see the show later this month with two buddies, who also grew up California.

“I’m going to have to get a Magic jersey for the occasion,” he says. “Magic transformed the Lakers and the Lakers are my team.”

And it seems Magic and Bird, for the moment, are transforming Broadway, too.